unfortunately, gilded metal and bonded bullet designs require high velocities to open up. nosler recommends at least 1800FPS for their accubond, partition, and Etip bullets to function properly. Speer recommended the same for their deep curl rifle bullets. unfortunately, real world tests have indicated to me, that this is also a low estimate, I have had Etips and partitions in various calibers fail to open more than minor mushrooming up to 2100FPS. for best performance, at least 2300FPS should be used, a velocity barely attainable from a 308 with 16 inch barrel when talking about a 180gr bullet.
considering this data I just stole from a different forum
Quote:
150 gr HPBT Win 748 loaded to a chamber pressure of 56.4K PSI WARM load 45 gr NOT a starting load. I chose 748 as the powder as it is most like NATO powder.
26" = 2918 FPS MP= 6.6K PSI ––99.6 % powder burnt -2836 ft/lbs
24" = 2873 FPS MP= 7.4K PSI ––––––––––––––––––––––––––––2750 ft/lbs
22" = 2823 FPS MP= 8.2K PSI ––––––––––––––––––––––––––––2655 ft/lbs
20" = 2766 FPS MP= 9.2K PSI ––98.7 % powder burnt -2548 ft/lbs
18" = 2700 FPS MP= 10.5K PSI ––––––––––––––––––––––––––––2428 ft/lbs
16" = 2623 FPS MP= 12.0K PSI -97% powder burnt ––––2291 ft/lbs
14" = 2531 FPS MP= 14.0K PSI ––––––––––––––––––––––––––2133 ft/lbs
12" = 2417 FPS MP= 16.7K PSI -94% powder burnt ––1946 ft/lbs
10" = 2273 FPS MP= 20.5K PSI ––––––––––––––––––––––––––1721 ft/lbs
8.0"= 2080 FPS MP= 26.0K PSI -87% powder burnt. -1441 ft/lbs
6.0"= 1800 FPS MP= 34.1K PSI -79.4% powder burnt -1080 ft lbs
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as you can see using w748 powder, which is on the lower end of average burn rate for the 308 cartridge loses nearly 450FPS from a standard 24" barrel to a 16 inch barrel. if a person wants to use gilded metal or bonded bullets effectively, they will still have to worry about velocity and still have to use a faster burn rate powder to make the most use of the short barrel. I stand by my post which you quoted, but took out of context. you ignored the point I made which corresponds with your post about bullet selection being key, and fail to take into account the velocity requirements of well crafted bullets.